Messages in this thread | | | From | Matthias Welk <> | Subject | Re: nfs slowdown since 2.5.4 | Date | Tue, 4 Jun 2002 17:56:54 +0200 |
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On Tuesday 04 June 2002 14:23, Trond Myklebust wrote: > >>>>> " " == Matthias Welk <welk@fokus.gmd.de> writes: > > Hi, since 2.5.4 I noticed a big slowdown in nfs. It seems that > > this is related to the changes in the nfs-lookup code, because > > now most traffic via nfs is for lookup- and getattr-calls as > > you can see in the attached tcpdump log. I'v also attached a > > log of nfsstat, which shows this problem too. > > Tough... Those extra checks are needed in order to ensure data cache > correctness on file open(). > > If you think you don't need them because the files that you are > reading are known never to change on the server, you can try mounting > with the 'nocto' mount option. >
I tried again with the 'nocto' mount option, although I can't be sure that the files will not change on the server, but the behaviour didn't change :-(
To get more info about this problem I compared the compile time and the nfs traffic between 2.4.18-4 and 2.5.20 on a RedHat 7.3 system. The sources (mosfet-liquid0.9.5.tar.gz - KDE style) were located on the local disc and the libraries were linked over nfs. The results attached to this mail show the big difference !
I hope you can do anything with it.
Greetings, Matthias. -- --------------------------------------------------------------- From: Matthias Welk office: +49-30-3463-7272 FHG Fokus mobile: +49-179- 1144752 Kaiserin-Augusta-Allee 31 fax : +49-30-3463-8672 10589 Berlin email : welk@fokus.fhg.de ----------------------------------------------------------------
#time to build on a RedHat 7.3 system with 2.4.18-4
real 1m1.301s user 0m50.920s sys 0m8.390s
lookup: 2820 getattr: 22 readdir: 96 frag: 66#time to build on a RedHat 7.3 system with 2.5.20
real 1m48.509s user 0m51.320s sys 0m12.790s
lookup: 287582 getattr: 2546 readdir: 1958 frag: 8465 | |